Indications, methodology, and interpretation of combined esophageal impedance-pH monitoring in children: ESPGHAN EURO-PIG standard protocol

A new formula proposal for placing pH-impedance catheters in pediatric patients

INTRODUCTION

Esophageal pH-impedance monitoring is a tool for diagnosing gastroesophageal reflux in children. The position of the pH catheter is essential for a reliable reading and the current formulas for calculating catheter insertion length are not completely accurate. The aim of the present study was to develop a new formula for adequate insertion of the pH catheter.

MATERIAL AND METHODS

A cross-sectional study was conducted on children that underwent pH-impedance monitoring and later radiographic control, to calculate the correct catheter insertion length. The documented variables were age, sex, weight, height, naris to tragus distance, tragus to sternal notch distance, sternal notch to xiphoid process distance, and initial insertion length determined by the Strobel and height interval formulas. A multivariate regression analysis was carried out to predict the final insertion length. Regression ANOVA and Pearson's adjusted R-squared tests were performed.

RESULTS

Forty-five pH-impedance studies were carried out, 53% of which were in males. The age and weight variables were not normally distributed. In the initial regression model, the variables that did not significantly correlate with the final insertion length were: sex (P 0.124), length determined by the Strobel or height interval formulas (P 0.078), naris to tragus distance (P 0.905), and tragus to sternal notch distance (P 0.404). The final equation: 5.6 + (height in cm * 0.12) + (sternal notch to xiphoid process distance * 0.57) produced an R2 of 0.93 (P 0.000).

CONCLUSIONS

This formula can be considered a valid option for placement of the pH-impedance monitoring catheter in pediatrics.

Utility of the Post-Reflux Swallow-Induced Peristaltic Wave Index and Mean Nocturnal Baseline Impedance for the Diagnosis of Gastroesophageal Reflux Disease Phenotypes in Children

(1) Objectives: Assessment of novel impedance parameters such as the post-reflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) have been proposed to enhance the accuracy of gastroesophageal reflux disease (GERD) diagnosis. We aimed to evaluate the clinical value of MNBI and the PSPW index in discerning different phenotypes of GERD in children. (2) Methods: We conducted a prospective, observational study that included 49 children aged 5-18 years, referred for MII-pH monitoring due to negative endoscopy and persisting gastroesophageal reflux symptoms despite acid-suppressant treatment. The PSPW index and MNBI were assessed along with conventional metrics. (3) Results: Using a receiver operating characteristic (ROC) curve analysis, MNBI (AUC 0.864) and the PSPW index (AUC 0.83) had very good performance in differentiating between non-erosive reflux disease (NERD) and functional phenotypes. The PSPW index (AUC 0.87) discriminated better between functional heartburn (FH) and reflux hypersensitivity (RH) compared to the MNBI (AUC 0.712). A PSPW cut-off value of 65% provided a sensitivity of 76.9% and a specificity of 90% in distinguishing FH and RH. The PSPW index (AUC 0.87) proved to have better performance than the MNBI (AUC 0.802) in differentiating between FH and non-FH patients. MNBI diagnosed FH with a sensitivity of 84% and a specificity of 80.6% at a cut-off value of 2563 Ω. (4) Conclusions: The PSPW index and MNBI are useful to distinguish between GERD phenotypes in pediatric patients.

The Utility of Novel pH-Impedance Monitoring Parameters (PSPW Index and MNBI) in Pediatric Gastroesophageal Reflux Disease Phenotypes-A Systematic Review

Background/Objectives: Researchers have proposed two novel impedance-pH parameters, mean nocturnal baseline impedance (MNBI) and the post-reflux swallow-induced peristaltic wave (PSPW) index, to enhance the diagnosis of gastroesophageal reflux disease (GERD) and enable better predictions of the effectiveness of anti-reflux therapies. This systematic review aims to synthesize the available evidence on the utility of the PSPW index and MNBI as diagnostic tools for pediatric GERD. Methods: A systematic search of studies reporting PSPW index and MNBI values in patients with GERD was performed in PubMed, Embase, Clarivate, Scopus, Cochrane and Google Scholar databases from their beginning until April 2024. The following terms were used: GERD, children, pediatric, PSPW and MNBI. Results: Eight studies were included, describing 479 patients ranging from 2 months to 17 years old over an 8-year period in 12 pediatric centers. Four studies demonstrated that children with pathological acid exposure have a significantly lower MNBI, with a good discriminatory ability to diagnose GERD. The PSPW index showed lower values in patients with reflux hypersensitivity (RH) compared to those with functional heartburn (FH). Conclusions: Patients with pathological acid exposure tend to exhibit lower MNBI and PSPW index values compared to those with normal acid exposure. MNBI and the PSPW index show promise as diagnostic tools in distinguishing between different GERD phenotypes. Further research is needed to establish standardized diagnostic criteria and optimize the clinical applicability in GERD diagnosis and management.

Study on Nocturnal Infant Crying Evaluation (NICE) and Reflux Disease (RED)

BACKGROUND

Nocturnal infant crying is often empirically treated with acid suppressants. The aim of this study was to evaluate the prevalence and characteristics of gastroesophageal reflux (GER) in infants with unexplained persistent crying.

METHODS

We enrolled all infants (0-12 months) referred for suspected GER disease who underwent esophageal impedance-pH monitoring (MII-pH) for unexplained persistent crying not improved by parental reassurance, dietary modification or alginate. Gastrointestinal malformation/surgery, neurological impairment and infections were exclusion criteria. Demographic and anthropometric parameters, GER symptoms and questionnaires (I-GERQ-R) and MII-pH data were recorded and analyzed. Normal MII-pH was defined when acid exposure was <3%, symptom index was <50% and symptom association probability was <95%. Acid exposure >5% and >10% was also considered. Statistical analysis was performed using Chi-Square and univariate and multivariable regression analysis.

RESULTS

We included 50 infants (median age 3.5 months) who fulfilled the study criteria: 30 (60%) had normal MII-pH. I-GERQ-R score was abnormal in 33 (66%) infants, and 21/33 (64%) had normal MII-pH (p = 0.47). In the 26 (52%) infants with nocturnal crying, MII-pH was normal in 16 (54%) (p = 0.82). Associated regurgitation (>3 or >10 episodes/die) did not predict abnormal MII-pH (p = 0.74, p = 0.82, respectively). Univariate and multivariable regression analysis did not identify any clinical variable significantly associated with abnormal MII-pH.

CONCLUSIONS

Infants with persistent unexplained and nocturnal crying should not be empirically treated with acid inhibitors.

Multichannel intraesophageal impedance with pH metry in Saudi children

BACKGROUND

Multichannel Intraesophageal Impedance with pH (MII-pH) provides complete characterization of gastroesophageal reflux (GER). The aim of this study was to report our experience in this relatively new technique, emphasizing the challenges in the performance and interpretation of the results.

METHODS

The study was conducted at King Khalid University Hospital at King Saud University in Riyadh. A retrospective review of the medical records of children who underwent MII-pH was performed. The procedure was performed and interpreted according to the recommended methodology. The impedance catheter was introduced nasally. The use of event markers and diary were explained to the accompanying person. At the end of the recording, the data were downloaded to the software analysis system.

RESULTS

MII-pH was performed on 98 children, and 16 studies were excluded from analysis for technical reasons. The median age was 32 (range 2-168) months and 44 (54%) were male. The prevalence of nonacid gastroesophageal reflux (NAGER), proximal extent of GER, and postprandial NAGER were 55%, 50%, and 70%, respectively. One hundred and fifty-three symptoms were reported during the study, but only two were significant.

CONCLUSION

The MII-pH was well-tolerated but the performance and interpretation were technically demanding. The main advantage was the detection of NAGER. However, the lack of normal values and the reliance on symptom association make the interpretation of the results challenging.

Simple Formula for pH/Impedance Probe Positioning in Children-Time to Update Standard Practice?

OBJECTIVE

To develop a novel formula for pH probe placement with adequate accuracy.

METHODS

Children (3-18 y) undergoing pH-metry were prospectively evaluated. Their height and corrected pH probe position under X-ray (2 vertebrae above the diaphragm) was recorded and the linear-regression analysis was performed to derive a novel formula. Its accuracy was checked on an additional group of prospectively included children. The success rate of a newly developed formula was estimated and compared to the performance of previously used formulae. The difference in the suggested placement of the probe (cm from nostrils) was calculated.

RESULTS

Based on 670 children with pH probe placed under X-ray, the following formula was developed using the linear-regression analysis: L = 0.184x + 4.4 (cm) (L = probe placement depth, x = body height). Its accuracy was confirmed on additional 111 children resulting in almost 85% success rate. The formula showed significant difference in the suggested placement from formulae used previously: +4.9 ± 0.8 cm, +2.4 ± 0.1 cm, +0.7 ± 0.6 cm, +1.1 ± 0.4 cm, +1.8 ± 0.3 cm, +2.2 ± 0.5 cm from the one by the Strobel, Moreau, Wilson, Nowak, Staiano-Clouse formulae, and the GOSH table with the calculated success rates of 1.8%, 43.2%, 65.8%, 77.5%, 65.8% and 54.1%, respectively. A table suggesting placement depth based on the body height was developed.

CONCLUSION

The present formula provides 85% success of pH probe placement in children ≥ 3 y suggesting its use in routine practice. More data are needed to confirm that probe adjustment under X-ray is unnecessary.

The Irritable Infant in the Neonatal Intensive Care Unit: Risk Factors and Biomarkers of Gastroesophageal Reflux Disease

OBJECTIVES

To determine risk factors for arching/irritability in high-risk infants and examine the significance of comorbidity and gastroesophageal reflux (GER) characteristics.

STUDY DESIGN

Retrospective analysis of 24-hour pH-impedance studies of symptomatic infants in a neonatal intensive care unit (ICU) (n = 516, 30.1 ± 4.5 weeks of gestation, evaluated at 41.7 ± 3.2 weeks postmenstrual age) was conducted. Comparisons were made between infants with >72 vs ≤72 arching/irritability events per day. We characterized risk factors for arching/irritability along with clinical, pH-impedance, and outcome correlates.

RESULTS

Of 39 973 arching/irritability events and 42 155 GER events, the averages per day were 77.6 ± 41.0 and 81.7 ± 48.2, respectively. Acid reflux and impedance bolus characteristics were not significantly different between infants with >72 and ≤72 arching/irritability events (P ≥ .05). The odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for postmenstrual age and weight at evaluation were significant for risk factors of preterm birth (2.3 [1.2-4.4]), moderate or severe neuropathology (2.0 [1.1-3.6]), and presence of oral feeding at testing (1.57 [1.07-2.30]).

CONCLUSIONS

Acid GER disease is unlikely the primary cause of arching/irritability and empiric treatment should not be used when arching/irritability is present. Prematurity and neurologic impairment may be more likely the cause of the arching/irritability. Arching/irritability may not be a concern in orally fed infants.

How Best to Estimate Insertion Length of Multichannel Intraluminal Impedance pH Probes in Children

OBJECTIVE

To assess the reliability of the KidZ Health Castle formula (KHC-F) to determine the correct probe position of a multichannel intraluminal impedance pH.

STUDY DESIGN

A retrospective cohort study was performed on 222 children between 1 month and 18 years of age undergoing multichannel intraluminal impedance pH. The primary outcome was the comparison of the pH sensor location determined by the KHC-F with the radiological target position. The margin of error was defined as 1 cm from the target position. Performance of the KHC-F and existing formulas was determined via the percentage with a correct position, mean error, 95% limits of agreement (Bland-Altman plots), and Spearman correlation. A post hoc analysis was performed with an updated KHC-F v2, subtracting -0.5 cm from the KHC-F.

RESULTS

Positioning with KHC-F was correct in two-thirds of the participants, with a very strong correlation (ρ = 0.91) with the target position. Bland-Altman plots showed good agreement between KHC-F and target position (mean error of -0.44 cm, lower limit -3.2 cm, upper limit 2.3 cm). A post hoc analysis with the KHC-F v2 showed a correct positioning in 74% of patients. Comparison with other formulas showed a stronger performance of KHC-F and KHC-F v2 on correct positioning, mean error, and 95% limits of agreement.

CONCLUSIONS

The KHC-F leads to reliable results. KHC-F v2 outperforms all other existing formulas in children, thereby reducing the need for repositioning and the amount of x-ray exposure. The age distribution of the sample may be a limitation, as well as the retrospective nature of the study.

Change of Sleep Stage during Gastroesophageal Reflux in Infants

INTRODUCTION

This study intended to explore the existence of a temporal association of changes of sleep stage and gastroesophageal reflux (GER) in infants.

MATERIALS AND METHODS

Documentation of sleep stage and GER was conducted via the use of synchronized polygraphic recording combined with impedance-pH-metry in 15 infants. The total recording-time (Rt) was divided into GER-"window-time" (five seconds before and after the onset of a GER episode), "remaining GER time", and "GER-free time", and analyzed for changes of sleep stage.

RESULTS

a total of 462 GER episodes were identified during Rt (151.1 h) in all infants. During 1.3 h of window-time; 61 changes of sleep stage (47/h); during 5.9 h of Remaining GER-time, 139 changes of sleep stage (24/h); and during 143.9 h of GER-free time, 4087 changes of sleep stage (28/h) were documented. Change of sleep stage was strongly associated with the onset of GER (p < 0.02 and p < 0.05, respectively).

CONCLUSIONS

There is a strong temporal association between sleep irregularities, i.e., changes of sleep and episodes of GER in infants. When dealing with disturbed sleep in infants, GER should be considered by caregivers.

Gastroesophageal reflux disease in children: What’s new right now?

Gastroesophageal reflux (GER) in children is very common and refers to the involuntary passage of gastric contents into the esophagus. This is often physiological and managed conservatively. In contrast, GER disease (GERD) is a less common pathologic process causing troublesome symptoms, which may need medical management. Apart from abnormal transient relaxations of the lower esophageal sphincter, other factors that play a role in the pathogenesis of GERD include defects in esophageal mucosal defense, impaired esophageal and gastric motility and clearance, as well as anatomical defects of the lower esophageal reflux barrier such as hiatal hernia. The clinical manifestations of GERD in young children are varied and nonspecific prompting the necessity for careful diagnostic evaluation. Management should be targeted to the underlying aetiopathogenesis and to limit complications of GERD. The following review focuses on up-to-date information regarding of the pathogenesis, diagnostic evaluation and management of GERD in children.

Prediction of refractory gastroesophageal reflux disease in young children

BACKGROUND

Many children respond to medical treatment for gastroesophageal reflux disease (GERD). However, some may require invasive intervention for refractory disease. Due to the lack of prognostic tools in children, this study aimed to develop a predictive model for refractory GERD.

METHODS

A retrospective review was performed in children with symptoms of GERD at a university hospital. Refractory GERD was defined as an unresponsive disease after optimal treatment with medication for >8 weeks. The predictive model was constructed based on clinical features and 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring results.

RESULTS

A total of 205 children were included with a median (IQR) age of 0.6 (0.3, 2.0) years. Over half of the patients (59.5%) had motor disabilities. Forty-four children (21.5%) were diagnosed with refractory GERD and subsequently underwent fundoplication. Multivariable analysis suggested that the refractory disease was associated with motor disabilities (OR: 5.35; 95% CI: 2.06-13.91), recurrent aspiration pneumonia (OR: 2.78; 95% CI: 1.24-6.26), prematurity with an onset of GERD at a post-conceptual age <40 weeks (OR: 6.76; 95% CI: 1.96-23.33), and abnormal total reflux episodes according to age (OR: 2.78; 95% CI: 1.24-6.19), but not the acid exposure time or symptom association analysis. The predictive model for refractory GERD based on associated factors revealed an area under the ROC curve of 76.8% (95% CI: 69.2%-84.3%) with a sensitivity of 77.3% and a specificity of 64% when applying a cutoff score of ≥2.5.

CONCLUSIONS

The predictive model, using clinical features and MII-pH, may be an additional tool to predict refractory GERD in young children.

Characteristics of gastroesophageal reflux disease in children with interstitial lung disease

BACKGROUND

Childhood interstitial lung disease (chILD) is a rare group of respiratory tract disorders. One of the factors suggested to be associated with its etiopathogenesis is microaspiration related to gastroesophageal reflux disease (GERD). The aim of the present study was to determine the frequency and characteristics of GERD in children with chILD, with a particular focus on proximal GER episodes.

METHODS

This was a prospective cross-sectional study. Consecutive patients with chILD underwent 24-h multichannel intraluminal pH-impedance monitoring. Different types of gastroesophageal reflux episodes (GER) were recorded and compared with regard to the GERD diagnosis.

RESULTS

Sixty-two children (median age of 1.22 years) were included. GERD was diagnosed in 20 (32.3%) of them. The GERD (+) and GERD (-) subgroups differed mainly in their esophageal exposure to acid content (2.9 vs. 1.0%, p = 0.02) and bolus exposure (3.0 vs. 1.4%, p < 0.0001), as well as total number of GER (72.5 vs. 42.0 p = 0.0004), acid GER (35.5 vs. 15.0 p = 0.004), and acid proximal GER (21.0 vs. 12.0 p = 0.02). There were no differences in the number of proximal GER comparing GERD (+) and GERD (-) subgroups.

CONCLUSIONS

The frequency of GERD seems to be relatively high in the population of children with chILD used in this study. However, it has not demonstrated an association between proximal GER and GERD diagnosis in chILD, which casts uncertainty over the microaspiration theory proposed to link the two diseases. The latter conclusion, however, needs to be confirmed using more accurate aspiration assessment methods.

Symptom Scores and pH-Impedance: Secondary Analysis of a Randomized Controlled Trial in Infants Treated for Gastroesophageal Reflux

BACKGROUND AND AIMS

To evaluate and compare gastro-esophageal reflux (GER) symptom scores with pH-impedance and test the effects of acid-suppressive medications with or without feeding modifications on pH-impedance in high-risk infants.

METHODS

Infant Gastroesophageal Reflux Questionnaire Revised (I-GERQ-R) and 24-hour pH-impedance data were analyzed from 94 infants evaluated in a tertiary care setting for GER disease. Longitudinal data from 40 infants that received randomized GER therapy (proton pump inhibitor [PPI] with or without feeding modifications) for 4 weeks followed by 1-week washout were analyzed. Relationships between I-GERQ-R and pH-impedance metrics (acid reflux index, acid and bolus GER events, distal baseline impedance, and symptoms) were examined and effects of treatments compared.

RESULTS

(A) Correlations between I-GERQ-R and pH-impedance metrics were weak. (B) I-GERQ-R sensitivity, specificity, and positive predictive values were suboptimal when correlated with pH-impedance metrics. I-GERQ-R negative predictive value (NPV) was high for acid symptom-association probability (NPV = 84%) and distal baseline impedence (NPV = 86%) thresholds. (C) PPI with feeding modifications (vs PPI alone) did not alter pH-impedance metrics or symptom scores (P > .05); however, bolus clearance metrics worsened for both treatment groups (P < .05).

CONCLUSIONS

In high-risk infants (1) I-GERQ-R may be a helpful clinical screening tool to exclude acid-GER disease diagnosis and minimize unnecessary acid-suppressive treatment, but further testing is needed for diagnosis. (2) Acid-suppressive therapy with feeding modifications has no effect on symptom scores or pH-impedance metrics. Clearance of refluxate worsened despite PPI therapy, which may signal development of pharyngoesophageal dysmotility and persistence of symptoms. (3) Placebo-controlled trials are needed in high-risk infants with objective pH-impedance criteria to determine efficacy, safety, and underlying mechanisms. Clinicaltrials.gov ID: NCT02486263.

Anti-reflux surgery in neonates and infants: analysis of indications, outcomes, and link to mortality among primary and secondary gastroesophageal reflux patients

Background

The indications and benefits of anti-reflux surgery (ARS) in neonates and infants are uncertain. Prematurity, operation before 1 year of age, neurological impairment (NI), and chronic lung disease (CLD) are risk factors for surgical failure. We aim to document the indications, management, and outcomes of ARS in this age group and compare them among primary and secondary gastroesophageal reflux (GERD).

Results

Between January 2008 and December 2019, 24 males and 22 females had ARS; 13 (28.3%) for primary while 33 (71.7%) for secondary GERD. The mean gestational age was 34.6 weeks (range 24–41) and mean birth weight was 2000 gm (range 600–3300). The weight at time of referral ranged from 1.4 kg to 4 kg (mean 2.2 kg). There were no significant differences between the two groups regarding the previous data. The group of primary GERD presented mainly with recurrent aspiration (n = 8), recurrent apnea (n = 5), and recurrent desaturations with or shortly after feeds (n = 4). The group of secondary GERD were referred for poor sucking with failure to thrive (FTT) (n = 25), recurrent aspiration (n = 20), and gastrostomy request (n = 14). The risk factors for secondary GERD were neurologically impaired (n = 22), post-esophageal atresia (EA) repair (n = 9), hiatus hernia (n = 4), thoracic stomach (n = 2), N-type tracheoesophageal fistula (TEF, n = 4), and congenital esophageal stenosis (CES, n = 4). The operations included open Nissen’s fundoplication (ONF) (n = 4) and modified open Thal’s fundoplication (MOTF) (n = 42). There were 8 mortalities in the secondary group, unrelated to surgery. Morbidities after Nissen’s fundoplication included wrap migration, gas bloat, and reoperation in one, laparotomy for intestinal obstruction (IO) in one. Following MOTF, there were two cases of transient recurrent GERD which improved with time and laparotomy in one for IO.

Conclusions

Diagnostic tests remain a challenge. Isolated TEF and CES may require fundoplication for staged management. Cases of the primary group did better with MTFO. Prematurity, CLD and age < 2 months were not significant risk factors for fundoplication failure or mortality. Neurological impairment was a risk factor for mortality.

Influence of laparoscopy-aided gastrostomy on gastroesophageal reflux in neurologically impaired patients using multichannel intraluminal impedance pH measurements

BACKGROUND

Development of gastroesophageal reflux disease (GERD) after gastrostomy remains debatable. Therefore, this study aimed to evaluate whether laparoscopy-aided gastrostomy (LAG) influence on the occurrence of GERD in neurologically impaired (NI) patients. Furthermore, we investigated whether preoperatively excluding NI patients with GERD can reduce the number of patients requiring subsequent anti-reflux surgery (ARS) after LAG.

METHODS

This retrospective study included 35 NI patients (median age: 11.0; interquartile range 5.0-23.5 years) who underwent LAG according to our criterion from October 2012 to June 2020 and MII-pH before and after LAG. MII-pH parameters were compared in all patients and among three age groups between before and after LAG.

RESULTS

There were no significant differences in MII-pH parameters before and 1 year after LAG in all patients, and no patient underwent subsequent ARS. Only one paediatric patient with 64 number of reflux episodes before LAG required subsequent ARS 3 years after LAG.

CONCLUSIONS

Generally, LAG did not influence the postoperative GERD at 1 year after LAG, and our criteria could reduce the number of patients requiring subsequent ARS. However, paediatric NI patients with higher number of reflux episodes in preoperative MII-pH study may need careful long-term follow-up after LAG.

Low Mean Nocturnal Baseline Impedance is Associated With a Pathological Acid Exposure Time in Children

BACKGROUND

The baseline impedance (BI) and the mean nocturnal baseline impedance (MNBI) serve as markers of mucosal integrity in patients with pathologic acid exposure time (AET). This work aims to investigate the association between the BI and MNBI with the AET in children.

METHODOLOGY

A retrospective study was performed in children ≤18 years old with suspicion of gastroesophageal reflux disease who underwent both endoscopy and pH-impedance monitoring (pH-MII). Esophagitis was graded according to the Los Angeles classification. The pathological AET was determined depending on the age (≥5% in patients >1 year and ≥10% in those ages ≤1 year). For the BI, 60 s measurements were taken every 4 h, and for the MNBI, 3 10 min measurements were taken between 1.00 and 3:00 am; then, they were averaged. The means of BI and MNBI were compared with each other, with the AET, and other variables.

RESULTS

Sixty-eight patients were included, 25% of patients presented pathological AET. The mean of the MNBI was higher than BI in channels 6 (2195 vs 1997 Ω, P = 0.011) and 5 (2393 vs 2228 Ω, P = 0.013). BI and MNBI at channel 6 were lower in patients with pathological AET than in those with normal AET (1573 vs 2138 Ω, P = 0.007) and (1592 vs 2396 Ω, P = 0.004), respectively.

CONCLUSIONS

Children with pathological AET had lower impedance values than those with normal AET. BI and MNBI measurements should be part of the routine MII-pH assessment in children.

Esophageal impedance baseline in infants with bronchopulmonary dysplasia: A pilot study

BACKGROUND

Bronchopulmonary dysplasia (BPD) may induce gastroesophageal reflux (GER). Esophageal impedance baseline values (BI) reflect mucosal inflammation. Our aim was to evaluate BI levels in preterm infants with BPD compared with those without BPD and to identify BI predictors.

METHODS

This is a retrospective pilot study including infants born <32 weeks' gestational age (GA) who underwent esophageal multichannel intraluminal impedance (MII)-pH. Univariate/multivariate analysis were performed to compare data between BPD and non-BPD infants and to identify BI predictors. A subgroup analysis was performed in infants born <29 weeks' GA, at highest risk for BPD.

RESULTS

Ninety-seven patients (median GA 28^5/7 weeks, mean postnatal age 49 days, 29 with BPD), were studied. BPD infants had significantly lower birth weight compared with non-BPD infants (750 vs. 1275 g), were more immature (27^4/7 vs. 29^0/7 weeks GA), were older at MII-pH (79 vs. 38 days) and received less fluids during MII-pH (147 vs. 161 ml/kg/day). The same findings were found in the group of 53 infants born <29 weeks. BPD versus non-BPD infants had significantly lower BI (2050 vs. 2574 ohm, p = 0.007) (<1000 ohm in five BPD infants vs. one non-BPD) whereas the other MII-pH parameters were not significantly different. Multiple regression analysis found that increasing chronological age was positively associated with BI (B = 9.3, p = 0.013) whereas BPD was associated with lower BI (B = -793.4, p < 0.001).

CONCLUSIONS

BPD versus non-BPD infants had significantly lower BI despite similar MII-pH data. BPD and chronological age predicted BI, whereas only BPD predicted BI in the most immature infants.

Belching in children: Prevalence and association with gastroesophageal reflux disease

BACKGROUND

Excessive belching is frequently reported in adult patients with gastro-oesophageal reflux disease (GORD) and dyspepsia. Although postprandial gastric belching (GB) is considered a physiological mechanism for gastric venting, supra-gastric belching (SGB) is considered a distinct behavioural disorder. We aimed to define the prevalence of different types of belching and its association with reflux disease in paediatric patients.

METHODS

We retrospectively analysed reflux monitoring studies from 287 patients (median age: 7.0 years; interquartile range 3.0-11.3 years) with a suspicion of GORD. Based on oesophageal acid exposure time (AET) patients were divided in 3 groups: (a) physiological AET, (b) borderline AET and (c) pathological AET. MII-pH studies were manually edited and reflux disease parameters were measured together with quantification of GB and SGB.

KEY RESULTS

Two hundred one children (70.0%) had physiological AET (median: 0.8; interquartile range 0.3-1.6), 52 (18.1%) had borderline AET (median: 4.2; interquartile range 3.4-5.3) and 34 (11.9%) had pathologic AET (median: 10.7; interquartile range 9.1-14.2). Gastric belching was observed in all studies. Gastric belching related reflux was more frequently observed in patients with borderline and pathological AET (p < 0.001). This was more common in older children. SGB were observed in only 7 (2.4%) children (age range: 8-17years) in our population and all patients had Physiological AET. Only 3 (1%) patients had pathological number of SGB (>13/24 h).

CONCLUSIONS AND INFERENCES

Gastric belching related reflux is observed in children with increased AET. SGB is very rare in the paediatric population.

Devices for esophageal function testing

BACKGROUND AND AIMS

Esophageal function testing is an integral component of the evaluation of refractory GERD and esophageal motility disorders. This review summarizes the current technologies available for esophageal function testing, including the functional luminal imaging probe (FLIP), high-resolution esophageal manometry (HRM), and multichannel intraluminal impedance (MII) and pH monitoring.

METHODS

We performed a MEDLINE, PubMed, and MAUDE database literature search to identify pertinent clinical studies through March 2021 using the following key words: esophageal manometry, HRM, esophageal impedance, FLIP, MII, and esophageal pH testing. Technical data were gathered from traditional and web-based publications, proprietary publications, and informal communications with pertinent vendors. The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy.

RESULTS

FLIP is a high-resolution impedance planimetry system used for pressure and dimension measurement in the esophagus, pylorus, and anal sphincter. FLIP provides complementary information to HRM for esophageal motility disorders, especially achalasia. The Chicago classification, based on HRM data, is a widely adopted algorithmic scheme used to diagnose esophageal motility disorders. MII detects intraluminal bolus movement and, combined with pH measurement or manometry, provides information on acid and non-acid gastroesophageal reflux and bolus transit in patients with refractory GERD and for preoperative evaluation for anti-reflux procedures.

CONCLUSIONS

Esophageal function testing techniques (FLIP, HRM, and MII-pH) have diagnostic and prognostic value in the evaluation of esophageal motility disorders and refractory GERD. Newer technologies and classification systems have enabled an increased understanding of these diseases.

Oesophageal pH-Impedance for the Diagnosis of Gastro-Oesophageal Reflux Disease: Validation of General Population Reference Values in Children with Chronic Neurological Impairments

Diagnosis of gastro-oesophageal reflux disease (GORD) in children with chronic neurological impairment (NI) remains a clinical challenge. The study aimed to validate the relevance of the reference values used to assess gastro-oesophageal reflux (GOR) in children with NI and to determine the optimal cut-off level of the pH-impedance parameter with the best predictive value for outcomes associated with endoscopic assessments of the oesophagus. Sixty-seven children (32 male, 35 female; age: interquartile range, 5 years 6 months-14 years 10 months; median, 11 years 3 months) with NI were prospectively recruited for the study. The exclusion criteria were previous fundoplication and lack of consent for the study. All patients underwent evaluations for GOR disease, including pH-impedance and gastroscopy. Based on endoscopy, oesophagitis was diagnosed in 22/67 children (32.8%); 9/67 (13.4%) were classified as having Hetzel-Dent grade III or IV. GOR was present in 18/67 children (26.9%), as determined by pH-impedance. Patients with endoscopic lesions had a significantly higher number of total reflux (p = 0.0404) and acidic episodes (p = 0.0219). The total number of reflux episodes, with a cut-off level of 44 episodes, was the pH-impedance parameter most strongly predictive of the presence of lesions in gastroscopy (specificity: 50%, sensitivity: 73%). These findings suggest that endoscopic lesions may be present in children with chronic NI with a low number of GOR episodes, as recorded by pH-impedance. The use of standardised reference norms determined for the general population may underestimate GOR episodes in this group of patients.

Plasma dosage of ghrelin, IGF-1, GLP- 1 and leptin related to gastric emptying and esophageal pH-impedance in children with obesity

PURPOSE

The main aim of the study was to assess the relationship between leptin, ghrelin, insulin-like growth factor 1 (IGF-1), and glucagon-like peptide 1 (GLP-1) blood levels and gastric motility in children with obesity compared to healthy children. Secondary aims were to assess the possible association between these hormones and obesity, reflux impedance parameters, reflux symptoms, other GI disorders, and quality-of-life scores within the same groups.

METHODS

Children with obesity plus GERD symptoms and 2 control groups of children with obesity without GERD and healthy lean children aged 4-17 years underwent an auxological evaluation, an assessment of gastro-intestinal symptoms and quality of life, hormonal dosages, and an evaluation of gastric emptying time (GET) through 13C-octanoic acid breath test.

RESULTS

No significant association was found between hormones and gastric motility. Leptin and ghrelin levels were significantly associated with obesity parameters. No significant differences were found between GET and hormones of the patients with obesity, either with or without GERD.

CONCLUSION

Although we found an association between auxological parameters and both leptin and ghrelin levels, this association did not imply an effect on the upper GI motility. Therefore, our hypothesis that alterations of these hormones in children with obesity could affect gastric emptying, triggering GERD, was not supported by our data.

The Role of Combined Multichannel Intraluminal Impedance-pH Monitoring in Infants with Brief, Resolved, Unexplained Events

PURPOSE

Data on the relationship between gastroesophageal reflux (GER) and brief resolved unexplained events (BRUE) in infants is scarce. The aim of this study was to identify the characteristics of combined multichannel intraluminal impedance-pH (MII-pH) monitoring in infants who have experienced BRUE.

METHODS

We conducted a prospective study of infants who were hospitalized on account of BRUE and required 24-hour MII-pH monitoring.

RESULTS

Twenty-one infants (mean age, 4.7 months; range, 0.9-8.9 months; male/female, 11/10) participated in this study. BRUE symptoms associated with GER were found in 10 infants (47.6%). Based on the RI on pH-metry alone, only 7 (33.3%) infants were diagnosed with GERD. More than 100 GER episodes detected by MII were found in 10 (47.6%) infants. Nineteen percent of infants were diagnosed with GERD based on both pH and MII.

CONCLUSION

Both acid and non-acid reflux seem to play a significant role in the pathogenesis of GER-related BRUE in infants.

Effects of upper airway obstruction or hypoxia on gastroesophageal reflux in newborn lambs

BACKGROUND

Although it is commonly accepted that upper airway obstruction (UAO) increases gastroesophageal reflux (GER), the link is poorly understood and insufficiently documented. In addition, while hypoxia is often encountered in infants with UAO, its consequences on GER are virtually unknown. The two aims of the present study were to characterize the effects of (1) UAO and (2) hypoxia on GER.

METHODS

Seventeen lambs underwent polysomnographic and esophageal impedance/pH-metry monitoring during UAO vs. a control condition (6 h, ten lambs) or 10% hypoxia vs. normoxic condition (3 h, seven other lambs).

RESULTS

Moderate-to-severe UAO was maintained throughout monitoring (inspiratory tracheal pressure of -13 (-15, -12) cm H₂O vs. -1 (-1, -1) cm H₂O in control condition, p = 0.005). While the number of GERs increased with UAO (2 (1, 4) vs. 0 (0, 3) in the control condition, p = 0.03), the increase was less than anticipated and inconsistent among the lambs. Also, sustained 10% hypoxia did not alter the number of GERs (2 (1, 3) vs. 0 (0, 5) in the control condition, p = 0.9).

CONCLUSIONS

The presence of an UAO for 6 h mildly increased the number of GERs, whereas hypoxia for 3 h had no significant effect.

IMPACT

The effect of upper airway obstruction and hypoxia on gastroesophageal reflux is poorly documented in the neonatal period. A moderate-to-severe upper airway obstruction for 6 h results in a mild, inconsistent increase in the number of gastroesophageal refluxes. Overall, a hypoxia of 10% for 3 h had no significant impact on gastroesophageal reflux. The prescription of an antireflux medication in infants with upper airway obstruction must not be systematic but rely on objective signs of a pathologic gastroesophageal reflux.

Clinical Experience With Performing Esophageal Function Testing in Children

OBJECTIVES

Pediatric high-resolution manometry (HRM) and 24-hour pH-impedance with/without ambulatory manometry (pH-MII+/-mano) tests are generally performed using adult-derived protocols. We aimed to assess the feasibility of these protocols in children, the occurrence of patient-related imperfections and their influence on test interpretability.

METHODS

Esophageal function tests performed between 2015 and 2018 were retrospectively analyzed. All tests were subcategorized into uninterpretable or interpretable tests (regardless of occurrence of patient-related imperfections). For HRM, the following patient-related imperfections were scored: patient-related artefacts, multiple swallowing and/or inability to establish baseline characteristics. For pH-MII(+/-mano), incorrect symptom registration and/or premature catheter removal were scored. Results were compared between age-groups (0-3, 4-12, and >12 years).

RESULTS

In total 106 HRM, 60 pH-MII, and 23 pH-MII-mano could be fully analyzed. Of these, 94.8% HRM, 91.9% pH-MII, and 95.7% pH-MII-mano were interpretable. Overall, HRM contained imperfections in 78.3% overall and in 8/8 (100%) in the youngest age group, 36/42 (85.7%) in 4 to 12 years and in 37/56 (66.1%) in children above 12 years; P = 0.011. These imperfections led to uninterpretable results in 4 HRM (3.8%), of which 3 were in the youngest age group (3/8, 37.5%). Imperfections were found in 10% of pH-MII and 17.4% of pH-MII-mano. These led to uninterpretable results in 5.0% and 4.3%, respectively. No age-effect was found.

CONCLUSIONS

Esophageal function tests in children are interpretable in more than 90% overall. In children under the age of 4 years, all patients had imperfect HRM and 3/8 tests were uninterpretable. HRM in older children and pH-MII+/-mano were interpretable in the vast majority.

Evaluation of Gastroesophageal Reflux Disease 1 Year after Esophageal Atresia Repair: Paradigms Lost from a Single Snapshot?

OBJECTIVE

To analyze the findings of both multichannel intraluminal impedance with pH (MII-pH) and endoscopy/histopathology in children with esophageal atresia at age 1 year, according to current recommendations for the evaluation of gastroesophageal reflux disease (GERD) in esophageal atresia.

STUDY DESIGN

We retrospectively reviewed both MII-pH and endoscopy/histopathology performed in 1-year-old children with esophageal atresia who were followed up in accordance with international recommendations. Demographic data and clinical characteristics were also reviewed to investigate factors associated with abnormal GERD investigations.

RESULTS

In our study cohort of 48 children with esophageal atresia, microscopic esophagitis was found in 33 (69%) and pathological esophageal acid exposure on MII-pH was detected in 12 (25%). Among baseline variables, only the presence of long-gap esophageal atresia was associated with abnormal MII-pH. Distal baseline impedance was significantly lower in patients with microscopic esophagitis, and it showed a very good diagnostic performance in predicting histological changes.

CONCLUSIONS

Histological esophagitis is highly prevalent at 1 year after esophageal atresia repair, but our results do not support a definitive causative role of acid-induced GERD. Instead, they support the hypothesis that chronic stasis in the dysmotile esophagus might lead to histological changes. MII-pH may be a helpful tool in selecting patients who need closer endoscopic surveillance and/or benefit from acid suppression.

Response to therapy among neonates with gastro-esophageal reflux is associated with esophageal clearance

BACKGROUND

Few studies evaluated the efficacy of pharmacological therapy for gastro-esophageal reflux disease (GERD) in newborns, whose safety has been questioned. Esophageal basal impedance (BI) is a marker of mucosal integrity, and treatment with proton pump inhibitors significantly increases BI in infants; however, no correlation with clinical improvement was reported.

AIMS

To evaluate the relationship between BI and other esophageal pH-impedance parameters and clinical response to therapy in newborns with GERD.

STUDY DESIGN

Multicenter retrospective study.

SUBJECTS

Infants who received omeprazole or ranitidine for GERD.

OUTCOME MEASURES

Complete response to therapy was defined as symptom decrease by ≥50% compared to baseline, partial response as symptom decrease <50%, no response as no symptom decrease based on chart analysis. Response to therapy was assessed 2 and 4 weeks after the onset of therapy. Univariate and multivariate statistics were performed to assess associations between response to therapy and clinical/pH-impedance parameters.

RESULTS

We studied 60 infants (51 born preterm): 47 received omeprazole, 13 ranitidine. Response to therapy was associated with decreasing esophageal clearance time: odds ratio 0.308, 95%CI 0.126-0.753, p = 0.010 at 2 weeks, odds ratio 0.461, 95%CI 0.223-0.955, p = 0.037 at 4 weeks.

CONCLUSIONS

Clinical response to therapy among infants with GERD was associated with esophageal clearance but not with esophageal BI level.

Does Combined Multichannel Intraluminal Impedance and pH (MII-pH) Testing Improve Clinical Outcomes in Children With Gastroesophageal Reflux Disease?

OBJECTIVES

The aim of the study was to investigate the role of combined multichannel intraluminal impedance and pH (MII-pH) testing in clinical management of children with gastroesophageal reflux disease (GERD) by exploring the impact of treatment changes made based on MII-pH testing results on symptoms and quality of life outcomes.

METHODS

All patients (<18 years) referred to the Sydney Children's Hospital for MII-pH testing were recruited. Patients were classified by acid suppression therapy (AST) status (on AST and off AST) and changes in medical and surgical management were evaluated. Validated questionnaires (Pediatric Gastroesophageal Symptom and Quality of Life Questionnaire and Infant Gastroesophageal Reflux Questionnaire Revised) were administered at baseline at the time of MII-pH testing, and 4 weeks after treatment changes were made and questionnaire scores were compared.

RESULTS

Of the 45 patients recruited, 24 patients (53.3%) were off AST and 21 patients (46.7%) were on AST. MII-pH testing led to medication changes in 30 patients (66.7%). This included 15 of 24 (62.5%) in those off AST and 15 of 21 (71.4%) in those on AST. More than 98% of patients who had treatment changes showed a significant improvement in both symptoms and quality of life scores.

CONCLUSIONS

Our study is one of the first pediatric studies to evaluate the clinical validity of MII-pH testing in the pediatric population referred for suspected GERD, and its ability in guiding clinical management. Our study has shown that treatment decisions guided by and based on results of MII-pH testing led to a significant improvement in symptoms and quality of life in infants and children with GERD.

Distress in Infants and Young Children: Don't Blame Acid Reflux

OBJECTIVE

The role of gastroesophageal reflux (GER) causing distress in infants is controversial but acid inhibitors are often empirically prescribed. We evaluated the relation between distress assessed by the Face, Legs, Activity, Cry, Consolability (FLACC) scale and GER in infants.

METHODS

We analyzed multiple intraluminal impedance-pH (MII-pH) monitoring tracings of infants with persistent unexplained fussiness or distress. Symptoms occurring during investigation were scored by parents using the FLACC scale and were grouped as "distress" episodes.

RESULTS

We recruited 62 children (ages 15 days to 23 months, median age 3.5 months). During MII-pH, 452 episodes of distress were registered: 217 (48%) were temporally associated with GER and 235 (52%) were not, with no difference in the median value of FLACC between the 2 groups. Infants with abnormal acid exposure index had a significantly lower FLACC compared with the group with acid reflux index <7% (P < 0.001). When associated with symptoms, GER occurred significantly more often before than simultaneously or after an episode of distress (P = 0.001). Age, proximal extension, and duration of GER did not correlate with FLACC scores. Episodes of distress associated with nonacid reflux presented a significant higher FLACC compared with the ones with acid content (FLACC 6 vs 5, P = 0.011). In infants, episodes of distress do not significantly correlate with GER.

CONCLUSIONS

No difference in infant distress was noted between proximal and distal GER. Non-acid reflux is perceived at least as painful than acid GER. Our results stress that acid inhibitors should not be started in infants presenting distress unless a clear association with acid GER is demonstrated.

Gastroesophageal reflux disease in pediatric esophageal atresia: Assessment of clinical symptoms and pH-impedance data

BACKGROUND

Esophageal atresia (EA) is the most common congenital anomaly of the gastrointestinal tract. Gastroesophageal reflux disease (GERD) is a frequent and lifelong problem in these patients. GERD can be asymptomatic and the incidence of esophageal gastric and intestinal metaplasia (Barrett’s esophagus) is increased in adults with EA compared with the general population. Timely and accurate diagnosis of GERD is important to reduce long-term problems and this may be achieved by pH-impedance testing.

AIM

To assess symptoms and pH-impedance data in children after EA, in order to identify their specific features of GERD.

METHODS

This study was conducted from November 2017 to February 2020 and involved 37 children who had undergone EA via open surgical repair (51.35% boys, 48.65% girls; age range: 1-14 years, median: 4.99 years). GERD diagnosis was made based on multichannel intraluminal impedance/pH study and two groups were established: EA without GERD, n = 17; EA with GERD, n = 20. A control group was established with 66 children with proven GERD (68.18% boys, 31.82% girls; median age: 7.21 years), composed of a nonerosive reflux disease (referred to as NERD) group (n = 41) and a reflux esophagitis group (n = 25). Upper gastrointestinal endoscopy with a mucosal esophageal biopsy was performed on all patients.

RESULTS

The most frequently observed symptom in EA patients with GERD and without GERD was cough (70% and 76.5% respectively). The number of patients with positive symptom association probability in the EA groups was significantly larger in the EA without GERD group (P = 0.03). In the control reflux esophagitis group, prevalence of gastrointestinal symptoms was significantly higher than in the NERD group (P = 0.017). For both EA groups, there was strong correlation with index of proximal events (IPE) and total proximal events (EA with GERD: 0.96, P < 0.001; EA without GERD: 0.97, P < 0.001) but level of IPE was significantly lower than in GERD patients without any surgical treatment (P < 0.001). Data on distal mean nocturnal baseline impedance were significantly different between the EA with GERD group (P < 0.001) and the two control groups but not between EA without GERD and the two control groups.

CONCLUSION

Mean nocturnal baseline impedance may have diagnostic value for GERD in EA children after open surgical repair. IPE might be an additional parameter of pH-impedance monitoring.

Laryngeal signs and pH-multichannel intraluminal impedance in infants and children: The missing ring: LPR and MII-pH in children

OBJECTIVE

to investigate the reliability of laryngeal reflux finding score (RFS) and symptom index (RSI) in assessing gastroesophageal reflux (GER) in children and infants.

METHODS

patients with laryngeal or respiratory symptoms, who underwent laryngoscopy and esophageal pH-impedance (MII-pH) were recruited. RSI and RFS were correlated to MII-pH results. A RSI>13, RFS>7, acid exposure index>7%, total reflux episodes>100/24 h in infants or>70/24 h in children, or a positive symptom index or association probability, were considered pathological. Analysis considering age (</>12 months) was performed. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of the laryngeal scores were calculated.

RESULTS

197 children (median 53 months, 61 infants) were enrolled. MII-pH was pathological in 5/10 patients with RFS>7, and in 17/31 with RSI>13. RFS>7 had 3.9% sensitivity, 93% specificity, a PPV of 50 and a NPV of 34 in predicting GER disease. RFS was inversely associated to weakly acidic and proximal GER. RSI>13 had 13% sensitivity, 83% specificity, and a PPV and NPV similar to RFS. RSI was significantly associated with the number of acid reflux episodes, and, in infants, with bolus exposure index.

CONCLUSIONS

RSI and RFS aren't accurate in predicting GER in infants and children. Acid reflux relates to laryngeal symptoms, but neither acid, nor proximal and weakly acidic GER relate to laryngeal alterations.

Understanding gastrointestinal motility studies in pediatrics

Motility of the gut is affected by the nervous system, the endocrine system, smooth muscle cells, interstitial cells of Cajal, secretory mucosal cells, the immune system, and gut flora. Abnormal gastrointestinal motility can generate nonspecific symptom complaints that are refractory to standard treatment approaches. It is important to exclude anatomical obstruction or other causes for patients' symptoms prior to proceeding with motility evaluation. Motility studies that help to evaluate children with suspected motility problems include combined multichannel intraluminal impedance (MII) and pH recording, esophageal manometry, gastric emptying scinitigraphy, antroduodenal manometry, colonic manometry, and anorectal manometry. Many pediatric gastrointestinal motility evaluations should be completed in a pediatric motility center where specialized training is completed by physicians in this field. Indications for pediatric gastrointestinal motility studies and how the procedures are performed are addressed in this paper.

Detection of reflux-symptom association in children with esophageal atresia by video-pH-impedance study

BACKGROUND

Children with esophageal atresia (EA) have risk of gastroesophageal reflux disease (GERD), suggesting reflux monitoring for prompt management.

AIM

To evaluate GERD in children with EA and specific symptom association from combined Video with Multichannel Intraluminal Impedance and pH (MII-pH) study.

METHODS

Children diagnosed with EA with suspected GERD and followed up at King Chulalongkorn Memorial Hospital between January 2000 and December 2018 were prospectively studied. All underwent esophagogastroduodenoscopy with esophageal biopsy and Video MII-pH study on the same day. Symptoms of GERD which included both esophageal and extra-esophageal symptom were recorded from video monitoring and abnormal reflux from MII-pH study based on the statement from the European Paediatric Impedance Group. Prevalence of GERD was also reported by using histopathology as a gold standard. Endoscopic appearance was recorded using Los Angeles Classification and esophagitis severity was graded using Esohisto criteria.

RESULTS

Fifteen children were recruited with age of 3.1 (2.2, 9.8) years (40%, male) and the common type was C (93.3%). The symptoms recorded were cough (75.2%), vomiting (15.2%), irritability or unexplained crying (7.6%) and dysphagia (1.9%) with the symptom-reflux association of 45.7%, 89%, 71% and 0%, respectively. There were abnormal endoscopic appearance in 52.9%, esophagitis in 64.7% and high reflux score in 47.1%. Video MII-pH study has high diagnostic value with the sensitivity, specificity and accuracy of 72.7%, 100% and 82.4%, respectively.

CONCLUSION

Prevalence of GERD in children with EA was high. Video MII-pH study to detect GERD in children with EA had high diagnostic value with the trend of specific symptom association.

Effects on Gastroesophageal Reflux of Donkey Milk-Derived Human Milk Fortifier Versus Standard Fortifier in Preterm Newborns: Additional Data from the FortiLat Study

Background: Feeding intolerance is a frequent diagnosis in very preterm infants. As seen in the FortiLat trial, human milk fortification with the new donkey milk-derived human milk fortifier (DF) seems to improve feeding tolerance in these infants. The aim of this study was to evaluate the effects of using the DF compared with bovine milk-derived fortifier (BF) on gastroesophageal reflux (GER) in very low birth weight (VLBW) infants. Methods: Over a total of 156 preterm infants were enrolled into the FortiLat trial (GA <32 weeks and birth weight <1500 g) and randomized into the BF arm or DF arm, and we selected all infants with clinical signs of GER and cardiorespiratory (CR) symptoms. All the infants underwent CR and multichannel intraluminal impedance and pH (MII/pH) monitoring associated with gastric ultrasound to evaluate GER and gastric emptying time. Results: 10 infants were enrolled, and 5 were in the DF arm. At MII/pH, infants enrolled into the DF arm showed a lower GER frequency than BF arm infants (p = 0.036). Half gastric emptying time was similar in DF and BF arm infants (p = 0.744). Conclusion: The use of donkey-derived human milk fortifier reduced the GER frequency and consequently should be recommended in infants with feeding intolerance.

Apnea in preterm neonates: what's the role of gastroesophageal reflux? A systematic review

A causal relationship between gastro-esophageal reflux (GER) and apnea in preterm infants has been frequently hypothesized and is currently debated. The present study aims at reviewing the currently available scientific evidence, in order to clarify the role of GER on the occurrence of apnea and to help improving the clinical management of apneic preterm neonates. We performed a systematic literature search to identify all the clinical studies on preterm neonates that properly assessed the relationship between apnea and GER. Two-hundred and fifty-two papers, including 32 reviews and meta-analysis, were screened. Out of them, only 7 were included in the final analysis according to the selected criteria. Among them, 3 studies reported an increased frequency of apnea after reflux compared to reflux-free period and 4 denied a significant temporal relation. In conclusion, a minority of apneic events occurs soon after GER episodes. Whether this happens by chance or because of a causal relationship is still impossible to define. Based on the available data, empirical treatment with acid inhibitors is not recommended in neonates with apnea unless a proven temporal relation is shown by simultaneous esophageal pH-impedance and polysomnography or cardiorespiratory monitoring and in the absence of a clear clinical benefit.

Multichannel Intraluminal Impedance and pH Monitoring: A Step Towards Pediatric Reference Values

Background/Aims

Combined multichannel intraluminal impedance and pH monitoring (MII/pH) is considered the most accurate test to detect gastroesophageal reflux (GER), however lacking reference values. We aim to determine reference values for the pediatric population and to correlate these values with age and postprandial/fasting period.

Methods

We evaluated MII/pH traces from patients (newborns, infants, and children) admitted to 3 Italian hospitals and who underwent MII/ pH for suspected GER disease. Patients with MII/pH traces that showed significant symptom-reflux associations and/or a pathological reflux index (> 6% for newborns and infants, > 3% for children) were excluded. Traces were analysed in their entirety, and in the postprandial period (first hour after a meal) and the fasting period (the following hours before the next meal) separately.

Results

A total of 195 patients (46 newborns, 83 infants, and 66 children) were included. Age positively correlated with frequency of acidic GER events (r = 0.37, P < 0.05) and negatively associated with weakly acidic GER events (r = 0.46, P < 0.05).

Conclusions

This study describes the distribution of MII/pH values in a pediatric population with normally acidic GER exposure and no significant association between GER events and symptoms. These MII/pH values may be used as reference values in clinical practice for a corrected GER disease diagnosis in the pediatric population.

Association between body positioning and gastroesophageal reflux in paediatric age

AIM

Postural measures are frequently recommended for gastroesophageal reflux (GER) symptoms, despite limited evidence. This was the first study to assess the impact of upright and recumbent body positions on GER episodes in children and adolescents, not just infants.

METHODS

We retrospectively assessed the pH-impedance parameters of paediatric patients referred for possible GER-related symptoms to two hospitals in Naples and Rome, Italy, from September 2016 to September 2018. Data were separately obtained for the time that the patients spent in upright and recumbent positions.

RESULTS

Data from 187 patients under the age of 18 were collected, at a mean age of just over seven years. We found that the acid exposure time was stable irrespective of changes in body position (P > .05). The mean number of reflux episodes per hour was 2.99 during the upright position and 1.21 during the recumbent position (P < .05), and the mean oesophageal acid clearance time was 44.4 and 93.4 seconds, respectively (P < .05).

CONCLUSION

Most paediatric patients experienced reflux in the upright rather than recumbent position, probably as a result of frequent transient lower oesophageal sphincter relaxations while they were awake. In particular, our findings provide new insights into postural measures for reflux in children and adolescents.

Characterization of Upper Gastrointestinal Motility in Infants With Persistent Distress and Non-IgE-mediated Cow's Milk Protein Allergy

BACKGROUND

Persistent crying in infancy is common and may be associated with gastroesophageal reflux disease (GERD) and/or non-IgE-mediated cow's milk protein allergy (CMPA). We aimed to document upper gastrointestinal motility events in infants with CMPA and compare these to findings in infants with functional GERD.

METHODS

Infants aged 2 to 26 weeks with persistent crying, GERD symptoms and possible CMPA were included. Symptoms were recorded by 48-hour cry-fuss chart and validated reflux questionnaire (infant GERD questionnaire [IGERDQ]). Infants underwent a blinded milk elimination-challenge sequence to diagnose CMPA. GERD parameters and mucosal integrity were assessed by 24-hour pH-impedance monitoring before and after cow's milk protein (CMP) elimination. C-octanoate breath testing for gastric emptying dynamics, dual-sugar intestinal permeability, fecal calprotectin, and serum vitamin D were also measured.

RESULTS

Fifty infants (mean age 13 ± 7 weeks; 27 boys) were enrolled. On the basis of CMP elimination-challenge outcomes, 14 (28%) were categorized as non-IgE-mediated CMPA, and 17 (34%) were not allergic to milk; 12 infants with equivocal findings, and 7 with incomplete data were excluded. There were no baseline differences in GERD parameters between infants with and without CMPA. In the CMPA group, CMP elimination resulted in a significant reduction in reflux symptoms, esophageal acid exposure (reflux index), acid clearance time, and an increase in esophageal mucosal impedance.

CONCLUSIONS

In infants with persistent crying, upper gastrointestinal motility parameters did not reliably differentiate between non-IgE-mediated CMPA and functional GERD. In the group with non-IgE-mediated CMPA, elimination of CMP significantly improved GERD symptoms, esophageal peristaltic function, and mucosal integrity.

[Comparative study of three methods in the diagnosis of laryngopharyngeal reflux in children]

Objective:To compare the consistency of RSI and RFS, pepsin detection and 24 h Dx-pH monitoring in the diagnosis of laryngopharyngeal reflux （LPR） in children. Method:A retrospective analysis was made of 76 children with suspicious LPR. A total of 65 children with suspicious LPR were finally diagnosed. RSI and RFS scales, pepsin detection and Dx-pH monitoring were performed simultaneously. The diagnostic consistency of the three methods was tested, and the sensitivity and specificity were calculated. Result:The sensitivity of pepsin detection, 24 h Dx-pH monitoring, RSI and RFS in the diagnosis of LPR in 76 suspected LPR patients were 95.31%, 66.15% and 84.62%, and the specificity were 100%, 81.82% and 72.73%. The pepsin detection was well consistent with the scale（Kappa>0.75）, pepsin detection and 24 h Dx-pH monitoring were in medium consistency（Kappa=0.467）, and 24 h Dx-pH monitoring and scale were in medium consistency（Kappa=0.446）. Conclusion:Pepsin detection can be used as a reliable index for the diagnosis of LPR in children. It is objective, economical, non-invasive, comfortable and easy to spread.

Esophageal pH-impedance monitoring in children: position paper on indications, methodology and interpretation by the SIGENP working group

Multichannel intraluminal impedance pH (MII-pH) monitoring currently represents the gold standard diagnostic technique for the detection of gastro-esophageal reflux (GER), since it allows to quantify and characterize all reflux events and their possible relation with symptoms. Over the last ten years, thanks to its strengths and along with the publication of several clinical studies, its worldwide use has gradually increased, particularly in infants and children. Nevertheless, factors such as the limited pediatric reference values and limited therapeutic options still weaken its current clinical impact. Through an up-to-date review of the available scientific evidence, our aim was to produce a position paper on behalf of the working group on neurogastroenterology and acid-related disorders of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) on MII-pH monitoring technique, indications and interpretation in pediatric age, in order to standardise its use and to help clinicians in the diagnostic approach to children with GER symptoms.

Acid and bolus exposure in pediatric reflux disease according to the presence and severity of esophageal mucosal lesions

PURPOSE

The relationship between reflux index (RI) and bolus exposure parameters in multichannel intraluminal impedance (MII) has not been examined sufficiently among children. The significance of acid and bolus exposure in evaluating pediatric reflux disease (RD) was explored by focusing on mucosal lesions.

METHODS

We conducted MII-pH on 28 patients (median age 8 years) with suspected RD. We assessed relationships between RI and bolus exposure indices, and also compared acid and bolus exposures across patients grouped by endoscopic esophageal mucosal lesions.

RESULTS

RI correlated significantly with distal acid reflux events (r = 0.60), acid bolus exposure time (BET) (0.55), and bolus clearance time (BCT) (0.48). Significant differences were observed among the control, non-erosive RD (NERD), and erosive RD (ERD) groups in all acid and several bolus exposure indices (distal and proximal frequencies, and BCT), while no significant difference was apparent between NERD and ERD. Acid exposure tended to be more severe in high-grade than in low-grade ERD, while no similar tendency was found in any bolus parameters other than BCT.

CONCLUSIONS

MII-pH showed great potential for investigating the pathophysiology of pediatric RD, with RI revealing different correlations with variable bolus exposure indices. However, no specific parameters allowing precise discrimination between RDs or mucosal severities were identified.

Correlation between cardiorespiratory events and gastro-esophageal reflux in preterm and term infants: Analysis of predisposing factors

BACKGROUND

The association between cardiorespiratory events (CRE) and gastro-esophageal reflux (GER) among neonates is still controversial.

AIMS

To test such an association in preterm and term infants.

STUDY DESIGN

Prospective observational study.

SUBJECTS

Forty-seven infants with suspected GER and recurrent CRE admitted at a neonatal intensive care unit, who underwent simultaneous and synchronized 24-hour recording of heart rate (HR), peripheral oxygen saturation (SpO2) and pH-impedance monitoring (MII-pH). HR/SpO2 data were filtered to avoid artefactual episodes of hypoxia and hypoperfusion.

OUTCOME MEASURES

The main outcome measure was the symptom association probability (SAP), with a 2-minute time window. Infants with positive (>95%) and negative (≤95%) SAP index tests were compared by univariate and multivariate statistics.

RESULTS

Median gestational age at birth was 29^4/7 weeks, median age at study 36 days. We recorded 3341 GER events and 4936 CRE (4710 desaturations, 226 bradycardias); 609/4936 (12%) CRE were temporally associated with GER episodes: 338 preceded and 271 followed GER events. The SAP index was significant in 5/47 (11%) patients. The SAP index including only CRE following GER events was significant in 3/47 (6%). There was no significant difference in the number of acid, weakly acid, non-acid, pH-only events preceding or following CRE between infants with SAP-positive and SAP-negative tests. Infants with positive SAP-index tests compared to those with SAP-negative tests had lower weight gain in the three days preceding the test and tended to have lower birth weight.

CONCLUSIONS

GER and CRE were associated in <11% of patients. The evaluation of ponderal growth might be helpful in predicting such an association.

Standard protocol devised by the Japanese Pediatric Impedance Working Group for combined multichannel intraluminal impedance-pH measurements in children

Multichannel intraluminal impedance-pH measurements (MII-pH) are useful for evaluating acid and non-acid gastroesophageal reflux (GER). However, the use of MIH-pH is not yet established in Japan. The Japanese Pediatric Impedance Working Group (Japanese-PIG) convened to devise a standard protocol for MII-pH in Japanese children. The expert members of the Japanese-PIG collected data on pediatric MII-pH from the relevant literature in English, including the standard protocol of MII-pH presented by the European PIG, and the insights of international experts. The resultant consensus was included in the contents of the standard protocol of MII-pH. The standard protocol included standardization of the indication, methodology, and interpretation of MII-pH in Japanese children. The criteria for abnormal GER by MII-pH were defined using the Reflux Index and number of total reflux episodes independently in children aged < 1 year and those aged ≥ 1 year. Moreover, a significant relationship between GER and symptoms was identified using the symptom index and symptom association probability approach. We conclude that the current version of the protocol for MII-pH is tentative because it is not based on data from Japanese children. Further studies are needed to render this protocol clinically beneficial and expand its use in Japan.

What is the best method for calculating the optimal position of an esophageal pH probe in children?

In assessment of distal esophageal pH, the sensor of the probe should be placed above the upper border of the lower esophageal sphincter. There are several methods to estimate the distance from the nose where the probe should be fixed according to the patient's height. We studied the accuracy of these methods. Data of patients who underwent esophageal monitoring were collected prospectively. The esophageal pH electrode was set with the aid of fluoroscopy in all cases, considering the location recommended by the current guideline. Esophageal probe position and anthropometric data of each patient were recorded. We compared the actual esophageal pH electrode distance from the nose with that estimated by Nowak's, Strobel's, Staiano-Clouse's, and Moreau's formulae and the Great Ormond Street Hospital (GOSH) table. A total of 98 patients were included, with ages ranging from 2 months to 19 years old. The highest success rate (67%) for all age groups was achieved by Nowak's formula (3.2 + 0.2 × height in cm). Considering only children under 3 years old, the GOSH table reached the highest-yet probably overestimated-fraction of adequate predictions. A corrected Staiano and Clouse's formula (4.28 + 0.191 × height in cm) had a slightly lower success rate than Nowak's due to a poorer performance in younger children. In conclusion, Nowak's formula is the most accurate regardless of age. It can help reduce radiation due to systematic fluoroscopy, as well as the subsequent manipulation of the esophageal probe. However, it still leads to pH sensor misplacements in more than one-third of children. In consequence, a confirmatory X-ray is advisable even after using the formula.

The assessment of the esophageal motility of children with esophageal disorders by the detailed observation of the pH-multichannel intraluminal impedance waveform and baseline impedance: screening test potential

BACKGROUND

The present study aimed to evaluate whether the detailed observation of pH/MII waveforms and the analysis of baseline impedance (BI) values could detect esophageal dysmotility in pediatric patients with esophageal disorders.

PATIENTS AND METHODS

Eleven patients with congenital esophageal disorder in whom pH/MII was conducted from April 2011 to June 2015, were enrolled in this study. The diagnoses of the patients were as follows: postoperative esophageal atresia (EA), n = 6; esophageal achalasia (EAch), n = 4; and congenital esophageal stenosis (CES), n = 1. The characteristics of the pH/MII waveform, pathological GERD, BI value, and the average BI value of the 2 distal channels (distal BI; DBI) were analyzed in each disorder.

RESULTS

Two EA (33%) patients and one EAch (25%) patient were diagnosed with GERD. The mean DBI values of the EA, EAch and CES patients was 912 ± 550, 2153 ± 915 and 1392 Ω, respectively. The EA patients showed consistently low DBI values. One CES patient and two infantile EAch patients showed postprandial prolonged low DBI values. Whereas, the pH/MII waveforms of the adolescent EAch patients were difficult to interpret due to their extremely low BI values.

CONCLUSIONS

The present study demonstrated that the detailed observation of the pH/MII waveforms in all channels and the analysis of BI were useful for evaluating esophageal motility in children with congenital esophageal disorders. In particular, infantile patients with EAch showed DBI findings that were distinct from those of adult EAch patients. Considering the difficulty of performing esophageal manometry in young children, the detailed observation of the pH/MII waveform may help in the diagnosis of esophageal dysmotility in children.

Esophageal Impedance-pH Monitoring and Pharyngeal pH Monitoring in the Diagnosis of Extraesophageal Reflux in Children

Various clinical symptoms are attributed to extraesophageal reflux disease (EERD). Multichannel intraluminal impedance-pH monitoring (MII-pH) is considered to correlate symptoms with acid and nonacid gastroesophageal reflux (GER) events. Pharyngeal pH monitoring (Dx-pH) is considered to correlate the decrease in the pH level in the oropharynx with reported symptoms and to diagnose supraesophageal reflux. We aimed to assess the correlation between acid reflux episodes recorded by Dx-pH and GER detected via MII-pH in children with suspected EERD. The study enrolled 23 consecutive children (15 boys and 8 girls; median age 8.25 [range 3-16.5] years) with suspected EERD. MII-pH and Dx-pH were conducted concurrently in all patients. A total of 1228 reflux episodes were recorded by MII-pH. With the antimonic sensor placed inside the impedance probe, 1272 pH-only reflux episodes were recorded. Of these, 977 (76.81%) were associated with a retrograde bolus transit. Regarding GER, 630 full-column episodes extended to the most proximal pair of impedance sensors; 500 (83.33%) demonstrated an acidic character. The following acid reflux numbers were determined by the Dx-pH system: for pH < 4, n = 126; pH < 4.5, n = 136; pH < 5, n = 167; and pH < 5.5, n = 304, and for a decrease in pH > 10% relative to the baseline, n = 324. There was no significant correlation between the number of pharyngeal reflux episodes detected by Dx-pH and that of GERs identified by MII-pH. The proportion of oropharyngeal pH events that were temporally related to a GER episode increased with the extended pH criteria. The highest proportion was observed for a pH decrease of ≥10% from the baseline and did not exceed 5.2%. The application of the extended pH criteria in the Dx-pH system resulted in an increase in the number of diagnosed laryngopharyngeal refluxes; most were not temporally associated with GER episodes confirmed by MII-pH. Thus, the efficacy of the exclusive application of Dx-pH for supraesophageal gastric reflux diagnosis is uncertain.

Erythromycin and Reflux Events in Premature Neonates: A Randomized Clinical Trial

OBJECTIVE

Gastroesophageal reflux disease (GERD) in premature neonates may manifest as apnea, bradycardia, growth failure, aspiration, or feeding intolerance. Erythromycin ethylsuccinate (EES), is often used as a pro-kinetic in the management of GERD, despite lack of evidence or safety from randomized controlled trials. We sought to study the efficacy of enteral EES at a dose of 50 mg · kg · day in decreasing the frequency of gastroesophageal reflux events as determined by pH-multichannel intraluminal impedance (pH-MII) monitoring.

METHODS

In a randomized, double-blind, placebo-controlled trial, eligible premature neonates with clinical signs of GERD underwent 24-hour pH-MII monitoring. If >5 reflux events were identified on pH-MII, then subjects were randomized to receive either EES or placebo. Repeat 24-hour pH-MII was performed on day 7 of study treatment and compared to initial pH-MII.

RESULTS

Forty-three premature neonates were enrolled. Of those, 31 neonates were randomized, 15 to EES and 16 to placebo with a median (IQR) pretreatment total reflux events per 24 hours of 23 (16-40) and 29 (12-40), respectively. Day 7 total events per 24 hours decreased by 4 events in the EES group to 19 (15-33) and by 10 events in the placebo group to 19 (11-26) (P = 0.09). There were no differences in pretreatment and day 7 acidic and nonacidic reflux, proximal reflux, total or percent reflux time, median or longest bolus clearance time, or nurse-reported apnea events between groups.

CONCLUSIONS

Enteral EES did not decrease reflux events on 24-hour pH-MII at the dose studied. Therefore, it may be ineffective in the treatment of GERD in premature neonates.

Effects of Smoking Exposure in Infants on Gastroesophageal Reflux as a Function of the Sleep-Wakefulness State

OBJECTIVE

To determine whether perinatal smoking exposure is associated with gastroesophageal reflux (GER)-related changes in sleep-wakefulness states in neonates.

STUDY DESIGN

Thirty-one neonates, referred for the investigation of suspected GER, were recruited and underwent multichannel impedance-pH monitoring and synchronized 8- to 12-hour polysomnography. The infants' exposure to tobacco smoke was estimated by means of a urine cotinine assay. The total number, frequency (h^-1), and mean duration (minutes) of GER-pH (reflux events detected by the pH electrode only) and GER-imp (reflux events with bolus movement detected by impedance) events were determined. Intergroup differences (smoking-exposed group vs nonexposed group) were probed with nonparametric, unpaired Mann-Whitney U tests. A χ² test was used to assess a possible intergroup difference in bolus retrograde migration during GER-imp events.

RESULTS

According to the urine cotinine assay, 21 of the 31 neonates had been exposed to cigarette smoke during the perinatal period. The number (and frequency) of GER-imp was significantly greater (P = .016) in the exposed group (29 [0-90]) than in the nonexposed group (12 [2-35]). Migration of the esophageal bolus from the distal segment to the most proximal segment was significantly more frequent (P = .016) in the exposed group (83% of GER) than in the nonexposed group (41%). The GER pattern associated with smoking exposure was particularly obvious during Rapid eye movement sleep.

CONCLUSIONS

The more frequent occurrence and greater proximal migration of GER-imp in the smoking-exposed group (especially during rapid eye movement sleep) may have clinical relevance. Smoking exposure is a preventable risk factor for limiting the occurrence of GER in neonates.